package org.seckill.service.impl;

import org.apache.commons.collections.MapUtils;
import org.seckill.dao.SeckillDao;
import org.seckill.dao.SuccessKilledDao;
import org.seckill.dao.cache.RedisDao;
import org.seckill.dto.Exposer;
import org.seckill.dto.SeckillExecution;
import org.seckill.entity.Seckill;
import org.seckill.entity.SuccessKilled;
import org.seckill.enums.SeckillStatEnum;
import org.seckill.exception.RepeatKillException;
import org.seckill.exception.SeckillCloseException;
import org.seckill.exception.SeckillException;
import org.seckill.service.SeckillService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.DigestUtils;

import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Create by cheng on 2018/5/24 11:52
 */
@Service
public class SeckillServiceImpl implements SeckillService {

    private Logger logger = LoggerFactory.getLogger(this.getClass());

    @Autowired
    private SeckillDao seckillDao;

    @Autowired
    private RedisDao redisDao;

    @Autowired
    private SuccessKilledDao successKilledDao;

    //md5盐值，用于混淆MD5

    private final String slat = "fjasdflafjsaldfj&$^^%";

    @Override
    public List<Seckill> getSeckillList() {
        return seckillDao.queryAll(0, 4);
    }

    @Override
    public Seckill getById(long seckillId) {
        return seckillDao.queryById(seckillId);
    }

    @Override
    public Exposer exportSeckillUrl(long seckillId) {
        Seckill seckill = redisDao.getSeckill(seckillId);
        if (seckill == null) {
            seckill = seckillDao.queryById(seckillId);
            //存入redis
            redisDao.putSeckill(seckill);
        }
        if (seckill == null) {
            return new Exposer(false, seckillId);
        }

        Date startTime = seckill.getStartTime();
        Date endTime = seckill.getEndTime();

        //系统当前时间
        Date nowTime = new Date();
        if (nowTime.getTime() < startTime.getTime() ||
                nowTime.getTime() > endTime.getTime()) {
            return new Exposer(false, seckillId, nowTime.getTime(), startTime.getTime(), endTime.getTime());
        }
        //转化特定字符串的过程，不可逆
        String md5 = getMD5(seckillId);

        return new Exposer(true, md5, seckillId);
    }

    private String getMD5(long seckillId) {
        String base = seckillId + "/" + slat;
        String md5 = DigestUtils.md5DigestAsHex(base.getBytes());
        return md5;
    }




    /**
     * 使用注解控制事务方法的优点
     * 1：开发团队达成一致的约定，明确标注事务方法的编程风格
     * 2、保证事务方法的执行尽可能短，不要穿插其他的网路操作RPC/http请求或者剥离得到事务方法的外部
     * 3、不是所有的操作都需要事务,如只有一条修改操作，只有读操作不需要事务控制
     */

    @Override
    @Transactional
    public SeckillExecution executeSeckill(long seckillId, long userPhone, String md5) throws SeckillException, SeckillCloseException, RepeatKillException {
        if (md5 == null || !md5.equals(getMD5(seckillId))) {
            throw new SeckillException("seckill date rewrite");
        }
        //执行秒杀逻辑：减库存+记录购买行为
        Date nowTime = new Date();
        try {
            //记录购买行为
            int insertCount = successKilledDao.insertSuccessKilled(seckillId, userPhone);
            if (insertCount <= 0) {
                //重复秒杀
                throw new RepeatKillException("seckill is repeated");
            } else {
                //减库存
                int updateCount = seckillDao.reduceNumber(seckillId, nowTime);

                if (updateCount <= 0) {
                    throw new SeckillCloseException("seckill is closed");
                } else {
                    //秒杀成功
                    SuccessKilled successKilled = successKilledDao.queryByIdWithSeckill(seckillId, userPhone);
                    return new SeckillExecution(seckillId, SeckillStatEnum.SUCCESS, successKilled);
                }
            }
        } catch (SeckillCloseException e) {
            throw e;
        } catch (RepeatKillException e) {
            throw e;
        } catch (Exception e) {
            logger.error(e.getMessage(), e);
            //所有编译器异常 转化为运行期异常
            throw new SeckillException("seckill inner error" + e.getMessage());
        }



    }

    //抛出异常是为了告诉spring是否rollback，此处使用存储过程的话，就不需要抛异常了
    public SeckillExecution executeSeckillProcedure(long seckillId, long userPhone, String md5) {
        if(md5 ==null || !md5.equals(getMD5(seckillId))){
            return new SeckillExecution(seckillId,SeckillStatEnum.DATA_REWRITE);
        }
        Date killTime=new Date();
        Map<String,Object> map=new HashMap<String, Object>();
        map.put("seckillId",seckillId);
        map.put("phone",userPhone);
        map.put("killTime",killTime);
        map.put("result",null);
        //执行存储过程，result被赋值
        try {
            seckillDao.killByProcedure(map);
            //获取result
            int result = MapUtils.getIntValue(map, "result", -2);
            if(result==1){
                SuccessKilled successKilled=successKilledDao.queryByIdWithSeckill(seckillId,userPhone);
                return new SeckillExecution(seckillId, SeckillStatEnum.SUCCESS,successKilled);
            }else{
                return new SeckillExecution(seckillId,SeckillStatEnum.stateof(result));
            }
        } catch (Exception e) {
            logger.error(e.getMessage(),e);
            return new SeckillExecution(seckillId,SeckillStatEnum.INNER_ERROR);
        }
    }

    public static void main(String[] args) {
        System.out.println(new SeckillServiceImpl().getMD5(1000));
    }
}
